The present disclosure relates to an electromagnetic interference (EMI) shielding gasket, and more particularly, to an EMI shielding gasket for a surface mount technology (SMT).
Electromagnetic waves may be emitted outward from a circuit of electronic devices through the atmosphere, or be transmitted through an electric wire. Various electromagnetic waves generated from a circuit of an electronic device may degrade the performance of peripheral electronic devices, make noise with peripheral electronic devices, damage an image formed by peripheral electronic devices, decrease the service life of peripheral electronic devices, and cause a defect in peripheral electronic devices. Furthermore, such electromagnetic waves may affect human bodies.
EMI shielding gaskets are used to address these issues. EMI shielding gaskets are disposed within a gap of a panel, a terminal, or a case of electronic devices such as mobile phones, LCD monitors, and computers, to prevent electromagnetic waves from being emitted from the electronic devices. As electronic devices are miniaturized, EMI shielding gaskets may be attached through surface mount on a printed circuit board (PCB). Such EMI shielding gaskets for a surface mount technology are required to have high electrical conductivity, excellent soldering properties, high heat resistance, and excellent elastic resilient characteristics.
To mount an EMI shielding gasket on a printed circuit board through surface mount, solder cream is applied to the EMI shielding gasket, then, the EMI shielding gasket is positioned to contact the printed circuit board, and then, a reflow process is performed. At this point, the solder cream is melted to have low viscosity, and is moved up to a portion of the side surface of the EMI shielding gasket by its surface tension and solder-rising during the reflow process, and thus, the portion of the side surface of the EMI shielding gasket is soldered.
In this case, since the soldered portion of the EMI shielding gasket is fixed, elasticity of the soldered portion is decreased, and thus, elastic resilient force of the EMI shielding gasket is entirely decreased. Thus, the thickness of an electronic product may be increased according to a decreased amount of the elastic resilient force of the EMI shielding gasket.
In addition, when the solder cream is moved up to the portion of the side surface of the EMI shielding gasket, and the portion of the side surface is soldered, the amount of solder cream between the printed circuit board and the bottom surface of the EMI shielding gasket is reduced, and thus, the EMI shielding gasket comes off the printed circuit board, thereby causing a defect such as soldering failure. To address these issues, the amount of the solder cream is increased, and thus, its costs are increased.